The present invention relates to cover systems and methods and, in particular, to cover systems and methods particularly suited for preserving hardenable materials that are dispensed from a container having a spout, nozzle, or other irregularly-shaped dispensing outlet which cannot easily be resealed.
The present invention is of particular significance at covering an elongate member of unknown or variable size and shape, especially when the elongate member is of relatively small diameter. The present invention is of particular significance when used to cover an elongate dispensing member for contained materials, and that application will be described in detail below. The present invention may, however, have broader application as a cover for a gun barrel, toothbrush, marking pen, electrical switch, bolt threads, or the like.
The term xe2x80x9ccontained materialsxe2x80x9d as used herein refers to any material that remains in a flowable form when stored in a sealed container. For example, the contained material may be a lubricant such as grease contained in a grease gun. As briefly discussed above, the present invention is of particular significance when the contained material is a xe2x80x9chardenable materialxe2x80x9d that, when exposed to air, hardens or sets in a hardened form. Hardenable materials include adhesives, sealants, fillers, caulks, coatings, and the like.
Most hardenable materials are packaged, shipped, and displayed for sale in a sealed container to ensure that the material does not harden or set prior to initial use. The sealed containers in which many hardenable materials are sold may easily be resealed after the initial use to allow for further storage of any hardenable material not used during the initial use. For example, coatings such as paint are often packaged in cans having lids that may be removed and replaced to prevent contamination or hardening of the hardenable coating material.
However, many hardenable materials are sold in containers designed to facilitate application of the hardenable material but which make it difficult to reseal the container after the initial use. For example, hardenable materials such as adhesives, sealants, caulks, fillers, and some paint materials are often sold in tubes having a generally conical dispensing member that tapers down to a reduced diameter point. The dispensing member is cut, usually at an angle, to form an outlet opening, and the hardenable material is pushed or squeezed out of the tube through the dispensing member in a bead.
The thickness of the walls of the dispensing member is substantially constant; accordingly, by cutting the dispensing member along a desired cutting plane, the user may determine, within limits, the cross-sectional shape and area of the outlet opening. The ability of the user to select the desired cross-sectional shape and area of the outlet opening allows the user to control the size and shape of the bead in which the hardenable material is applied.
The use of a dispensing member as just described complicates the resealing of the container after the initial use. Because the dispensing member is intended to be cut at any one of a number of locations along its length, the exact geometry of the tip after the cut has been made is not known in advance. The fact that the dispensing member tapers to a reduced diameter point also complicates the mechanics of attaching the cover to the tip. In addition, the material from which such dispensing members are made is typically a low friction plastic, and the tip may also be contaminated by the hardenable material.
Accordingly, the consumer has been expected to devise or purchase a cover for the conical dispensing member through which hardenable materials are dispensed.
The Applicant is aware of a number of techniques and products that have been used in an attempt to seal the dispensing members of containers of hardenable material.
One such technique is simply to insert a nail or screw through the outlet opening into the dispensing member. The head of the nail or screw blocks the outlet opening and may, with certain hardenable materials, slow or prevent the hardening of the material remaining within the container. The nail or screw is removed to reopen the outlet opening to dispense hardenable material at a later time. This method does not form an adequate seal for many hardenable materials and thus allows the material to harden. In addition, the nail can rust and discolor the hardenable material within the container.
Another known method of resealing the dispensing member of a container of hardenable material is simply to cover the dispensing member with a metallic or plastic foil or the like. The foil is sometimes held in place using a rubber band. The foil does not form a reliable seal, and the foil tends to slip off of the tapered outer surface of the conical dispensing member, even with a rubber and or the like exerting pressure to hold the foil on the tip.
The Applicant and others have for several years sold an after-market product designed to engage a conical or tapered dispensing member in a manner that seals an outlet opening formed therein. This product is, in essence, a flexible cover member that is similar to a male condom. The flexible cover member defines an open end, a closed end, and an elongate wall portion generally in the shape of a tube extending between the open and closed ends. The cover member is manufactured and sold in a rolled configuration and then placed in an unrolled configuration when used to seal the dispensing member. When rolled, the inner wall of the closed end is exposed. The user brings this exposed inner wall into contact with the outlet opening and unrolls the cover member such that the elongate wall portion overlaps the outer surface of the dispensing member.
The cover material from which the cover member is formed is resilient and stretches somewhat as it is unrolled onto the dispensing member; this cover material also has a fairly high coefficient of friction. The resiliency and friction of the cover material in conjunction with the relatively large surface area over which the cover member engages the outer surface of the dispensing member function both to mechanically fix the cover member onto the dispensing member and to form a relatively airtight seal. The cover material may be any material that functions as described herein but is preferably latex or neoprene.
The flexible cover member as just-described has met with some market success but is subject to a number of problems that may have somewhat limited its acceptance in the market place.
Initially, to keep manufacturing costs down, the manufacturing processes and materials used to manufacture the flexible cover member are the desirably same as those used in the manufacture of male condoms. In particular, both products are manufactured by creating a mold having a plurality of mold projections that correspond to the inner dimensions of the product. The mold projections are dipped into liquid cover material and removed. The liquid cover material coats the mold projections and is allowed to harden. The product is then rolled off of the mold projection and packaged in the rolled form until use.
While this basic process works well for the relatively large diameter male condom, the relatively small diameter flexible cover member tends to unroll when removed from the mold projection. This tendency can be reduced somewhat by reducing the thickness of the walls of the cover member, and in particular the wall thickness at its closed end. However, when too thin, the latex becomes excessively permeable to air, which causes the hardenable material in the dispensing member to dry and harden.
The need thus exists for improved systems and methods for covering dispensing members for hardenable material having irregular or unknown geometries.
The present invention is a cover member for elongate members such as dispensing outlets for hardenable materials. The cover member defines an open end, a closed end, and an elongate wall extending between the open and closed ends. In one embodiment, a wall thickness of the cover member at the closed end is greater than a wall thickness of the cover member adjacent to the open end. In another embodiment, an inner projection is formed at the closed end. In yet another embodiment, an insert member is arranged in the closed end. In still another embodiment, the cover member comprises first and second wall layers defining the closed end and at least a portion of the elongate wall.